🔐 Introducing FileKey: encrypt and share files using passkeys—free, fast, and open source

We’ve built FileKey, an open source web app that lets you quickly encrypt and share files using passkeys—no accounts, no tracking, no backend servers. Just local, offline security powered by passkeys.

Try FileKey here: https://filekey.app/

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• Free and open source

• Use passkeys to encrypt and share files

• Store your passkey in a password manager or hardware security key

• AES-256 encryption (“Military-grade”)

• Zero knowledge, only you can access your files

• Offline capable

• Can be locally installed (progressive web app)

• Your data never leaves your device

• Fast, ultra-secure encryption and decryption

• No accounts, no tracking, no data collection

FileKey first requires the generation of a passkey, that will be stored on either your password manager or security key device, using the app’s domain as the relying party.

Once a passkey has been created, it can then pass a static message through WebAuthn which interacts with a PRF in order to generate a deterministic random value.

Using this deterministic random value, an HKDF with 256 bits of entropy is generated. The HKDF and a random salt is then used to derive a key to be used with AES-GCM.

The derived key is then used to encrypt and decrypt the file. A new derived key is used for each additional file.

All low-level cryptographic functions performed within this process are using the web’s built-in SubtleCrypto interface of the Web Crypto API. All encrypted files use a unique randomly generated salt, composed of a 16 byte hash.

For more detailed information, check out the “How it works” section in the FileKey menu.

Requirements

• A compatible password manager (iCloud, Google, etc) or a hardware security key that supports FIDO2 and PRF (like the YubiKey 5 and Bio Series). We strongly recommend you use a hardware security key if you care about decentralization.

• For hardware security keys, your browser and operating system needs to support WebAuthn and the PRF extension.

Try FileKey v1 here: https://filekey.app/

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